1. Field of the Invention
This invention relates to a coulter and knife assembly advantageously designed for the knife to be accurately and precisely adjusted to maintain a critical, close-coupled trailing relationship with the coulter.
2. Description of the Prior Art
The use of applicator assemblies incorporating coulters and knives for attachment to agricultural implements is well known. The coulter is used to slice through surface trash and grass, as well as the soil itself, and the knife follows closely behind, usually carrying a conduit for liquid or dry fertilizer or the like.
One basic problem with such assemblies is that as the coulter blade is diametrically worn down by normal use the front edge of the knife becomes more distantly spaced from the rear peripheral edge of the coulter, thus increasing the size of the gap between the coulter and the knife and making it easier for stemmy crop residue and other tough materials to enter and accumulate within the gap. This trash buildup inhibits proper action of the applicator as it moves through the soil.
Furthermore, as the coulter wears down, the depth of the knife relative to the coulter typically changes since the knife is normally constructed in such a way that it wears more slowly than the coulter. Unless the knife can be adjustably raised as the coulter wears, the knife may eventually project down below the coulter and snag debris pressed into the slice by the coulter.
A number of devices concerning coulter blades with adjustable knives have been proposed in the past. In general, however, these units have not been totally satisfactory.